Two styles of explanation could be invoked. One explains a phenomenon by
appeal to the next lower level of molarity. Empirical reductionism appeals to
the brain to explain a behavior. Nonempirical reductionism appeals to an
entity such as the mind as an explanatory anchor or causal entity.

A fundamentally different explanatory style appeals to phenomena at the same
level of molarity as the behavior to be explained. Because the cause of
reductionistic changes must eventuate back in the environment sooner or later,
correlative explanations could be seen as simply cutting out the middleman.

The important point here is whether or not anything is added by the
reductionistic causal entity, not whether or not causes are ultimately in the
environment